The third act of Swan Lake is considered one of the most difficult in the balletic cannon, requiring a dancer to twirl around 32 consecutive times. How its accomplished is as much a feat of physics as it is athleticism.
I’d totally go to more ballets if they actually included cannons.
Dancers also turn their heads a particular way when spinning – “spotting” (keeping your eyes focused on one spot for as long as you can while the rest of you is turning, and then whipping your head around quickly to catch back up with the turn) also helps keep momentum going. And it lowers the odds of falling over bang! on the floor from being dizzy. Martial artists utilize the same skill.